have all been found to increase IL-1 production or are thought for other reasons to 
function by means of IL-1. 
Early studies of IL-1 by Staruch and Wood (31) demonstrated an increase in the 
antibody response to bovine serum albumin in mice from 4-fold to 30-fold above the 
use of BSA alone. A single intraperitoneal injection could achieve this effect. 
We have investigated the potential adjuvant function of IL-1 in a murine lung cancer 
tumor system (32) which uses a weakly immunogenic tumor cell vaccine of line 1 
tumor. We evaluated human IL-1 alpha, recombinant human IL-1 beta, and the 
peptide fragment 163-171 of IL-1 beta. All were tested in combination with a vaccine 
of irradiated tumor cells. All three types of IL-1 molecules were capable of improving 
the vaccine’s effectiveness. The benefit of IL-1 was both dose dependent and duration 
dependent (the number of daily doses given). IL-1 functioned as a systemic adjuvant; 
that is, it was effective even when administered at a site distant from the vaccine. It 
was required that the IL-1 be administered during the 10 day period following the 
vaccine rather than being given at some point later. In this tumor model, mice 
receiving vaccine alone were only 0-20% tumor-free at the conclusion of the 
experiments. When eight daily doses of IL-1 were given along with the vaccine, 70- 
100% of the mice became tumor-free. An illustrative experiment from this work is 
shown in Table III. Both doses of IL-1 beta were highly effective as adjuvants given 
with the vaccine. These animals were weighed at the beginning and at the end of the 
8 day period of treatment with IL-1. The higher dose of IL-1 effected weight gain, 
probably by virtue of the anorexia known to occur with high doses of IL-1 (33). 
However, the lower dose of IL-1 was well tolerated without an effect on weight gain 
and continued to be highly effective. 
6roup Vaccine 
1 
2 3X10 5 TC 
3 3X10 5 TC 
4 3X10 5 TC 
The Adjuvant Effect of Il-lg 
Hean Survival 
Il-llfnq) /Days i S.E.l 4 
14.90 t 1.02 
17.00 1 0.97 
120 dl-8 33.80 1 3.66 b 
360 dl-8 40.00 ± 0.00 b 
Tumor Free/ 
Total (XV 
0/10 ( 0 ) 
0/10 (0) 
7/10 ( 70 ) c 
10/10 (100 ) d 
4 Statistical comparisons with group 2 are indicated. 
b p < .001 c p « .001, d p < .0004 
Recombinant DNA Research, Volume 15 
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